Re: [PATCH v3 1/2] dt-bindings: gpio: 74x164: Introduce the 'registers-default' property

[Fabio Estevam <festevam@xxxxxxxxx>]

Hi Linus,

On Tue, Jan 5, 2021 at 12:35 PM Linus Walleij <linus.walleij@xxxxxxxxxx> wrote:

> So should the ethernet PHY not just have some reset-gpios
> that it obtain and de-assert as part of probing?
>
> For example drivers/net/phy/mdio_bus.c has this:
>
>         /* de-assert bus level PHY GPIO reset */
>         gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_LOW);
>
> Other drivers can do the same.
>
> Deferred probe should ascertain that this GPIO driver gets
> loaded before the ethernet phy driver.

Thanks for your review. I investigated this further and it seems to me
that the issue is in drivers/net/phy/mdio_bus.c, so I am adding some
netdev folks.

The driver drivers/net/phy/mdio_bus.c and the yaml description says
that it only supports one bus level PHY GPIO reset via reset-gpios
property.

On the imx6ul-evk, there are two KSZ8081 PHYs in the same mdio bus, so
this is how I described it in dts:

https://pastebin.com/raw/xLjYUHdN

but the 'reset-gpios' properties are not found in this case. I think
we need to let drivers/net/phy/mdio_bus.c to search for 'reset-gpios'
also inside the mdio children.

My understanding is that adding phy-reset-gpios under each fec node is
deprecated.

Any suggestions?

Thanks,

Fabio Estevam